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Hoffman Amps Forum image Author Topic: Wrong wiring of the low input?  (Read 1852 times)

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Offline Leevi

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Wrong wiring of the low input?
« on: May 12, 2018, 12:38:49 pm »

I think the low input is wrongly drawn? When plugging to Low input no signal will go to V1b.
I think the tip and switch should be wired other way round?


http://nicosonic.com/sites/default/files/pics/Soldano%20HR50%20SL60%20+%20XL%20mod.jpg


/Leevi
« Last Edit: May 12, 2018, 01:14:10 pm by Leevi »

Offline sluckey

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Re: Wrong wiring of the low input?
« Reply #1 on: May 12, 2018, 01:14:05 pm »
Yep
A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!

Offline Leevi

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Re: Wrong wiring of the low input?
« Reply #2 on: May 12, 2018, 02:12:24 pm »
There are some other mismatches in the schematic.
The bridge rectifier cannot be grounded if the center tap is grounded.
Same thing with the heaters. 100 ohms resistors are not needed if CT is grounded.
/Leevi

 


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